A door handle apparatus, on which a Smart Entry System (trademark) is mounted, is known, in which, for example, it is recognized that a user approaches a vehicle or that the user gets out of the vehicle, on the basis of a communication between a portable device, carried by the user, and a transmission device of the vehicle, while it is detected that a door lock command or a door unlock command is inputted by the user relative to a vehicle door in order to automatically execute locking and unlocking operations. Such door handle apparatus is disclosed in JP3502848A.
As illustrated in FIGS. 9 and 10, according to the door handle apparatus disclosed in JP3502848A, an unlock sensor SULK for detecting an unlock command of a user is arranged at a holding portion 110, at which a hand of the user may be inserted between an outer panel 200 of a vehicle door and a door handle 100. Further, a lock sensor SLK for detecting a lock command of the user is arranged at an operational-portion extending portion 120, the operational-portion extending portion 120 being arranged at the door handle 100 to be adjacent to the holding portion 110 and extending from a portion for operating an opening and closing mechanism of the vehicle door. The lock sensor SLK and the unlock sensor SULK are electrostatic capacitance sensors, which detect a fluctuation of the electrostatic capacitance. The lock sensor SLK and the unlock sensor SULK detect the fluctuation of the electrostatic capacitance, which is generated when the hand of the user approaches a vicinity of each detection electrode of the lock sensor SLK and the unlock sensor SULK, and thereby determining that the lock command or the unlock command are inputted. More specifically, a value of electrostatic capacity CPANEL, which is established between the outer panel 200 of the vehicle door and the detection electrode of the lock sensor SLK, is set as a standard value, and when a value of electrostatic capacity detected by the lock sensor SLK does not fluctuate for a great extent from the value of electrostatic capacity CPANEL, it is determined that the unlock command is not inputted. When the hand of the user approaches the vicinity of the detection electrode, another electrostatic capacity CT is established between the detection electrode and the hand of the user so as to be in parallel with the electrostatic capacity CPANEL (i.e., CPANEL+CT). Therefore, when the value of the electrostatic capacity, detected by the lock sensor SLK, is increased by a level corresponding to the value of electrostatic capacity CT, it is determined that the lock command is inputted. The detection principle may be applied to the unlock sensor SULK. According to the door handle apparatus disclosed in JP3502848A, the lock sensor SLK and the unlock sensor SULK are arranged at different portions of the door handle 100. Therefore, the lock command and the unlock command are detected in response to an operation of the user who touches the different portions of the door handle 100.
According to the door handle apparatus disclosed in JP3502848A, however, as illustrated in FIG. 10, a lock detection electrode (the lock sensor SLK) is arranged at an end portion of an outer surface of the holding portion 110 (i.e., a surface of the holding portion 110 opposite from the outer panel 200). Therefore, when the user inserts his/her hand between the holding portion 110 and the outer panel 200 in order to unlock the vehicle door, and then pulls the door handle 100 in order to open the vehicle door, the user may accidentally touch a detection area of the lock sensor SLK with his/her hand. In such a case, both of the unlock command of the unlock sensor SLK and the lock command of the lock sensor SLK may be outputted simultaneously, and an appropriate command may not be inputted. Further, the user may touch the detection area of the lock sensor SLK with his/her hand when the vehicle door is opened, and thereby a locking operation may be unintentionally executed. Thus, an operation, which is not intended by the user, may be executed.
A need thus exists for a door handle apparatus, which is not susceptible to the drawback mentioned above.